Sega Genesis/MegaDrive

Many readers of this book probably remember the sheer exhilaration that we all felt when we saw Sonic the Hedgehog for the first time. The raw speed that the Sega Genesis console displayed was courtesy of nothing more than a 7.1 MHz Motorola 68000 processor—of the same sort you might have seen if you cracked open your early Apple Macintosh or Commodore Amiga (if you were lucky enough to own one of those beauties). As such, emulating a Genesis at full speed should not be too much to ask of a modern PC. Let’s install Gens, the best Genesis emulator available (which conveniently runs on Unix, the best OS available), and see what it can do.


Gentoo users need to become root and then run the command emerge gens.

Other Linux distributions.

If you’re using another Unix or Linux distribution, check your installation media and online package repositories for a binary build of Gens. Otherwise, visit the Gens project’s Sourceforge downloads page ( and download the most recent tarball under the “Gens Source Code / Gens WIP linux” heading (as of this writing, it was named gens-rc3.tar.gz). Save the file to your /tmp directory.

Make sure you have GTK+ version 2.4 or greater installed, then proceed as for ZSNES (i.e., uncompress the tarball, change into the resulting directory, and do the ./configure && make && make install dance).

Once Gens is installed, using it is as easy as using ZSNES—just change to your Genesis ROMs directory and launch Gens:

	gens &

This will pop up a display window and the Gens title bar. The first step is to click on the Option menu and select Joypads. (Make sure to check out [Hack #52] and [Hack #51] if you have a Saturn controller lying around.) If you are going to be using a gamepad with only a few buttons (e.g., four), you should probably change the drop-down box next to Player 1 from 6 buttons to 3 buttons. In any case, click on the A icon to the right of the drop-down box to configure your gamepad. Gens will prompt you to press a key (see Figure 4-32) to map to each Genesis controller button.

Mapping Genesis controller buttons to your keyboard in Gens

Figure 4-32. Mapping Genesis controller buttons to your keyboard in Gens

After setting up your gamepad and clicking on the OK button to save your configuration, you will probably also want to visit the Graphic menu and select a new Rendermode (I like Double, which simply makes the display window twice as large). You may also want to run Gens in fullscreen mode, in which case there is an option in the Graphic menu, or you can just press Alt+Return at any time to toggle fullscreen mode on or off. Now, click on the File menu and select Open ROM. This will bring up a very strange browser window, which you should use to navigate to your Genesis ROMs directory. Double-clicking on Filesystem in the left pane will allow you to browse in the right pane, and once you have found your Genesis ROMs directory, highlight it and click on the Add button, which will add the directory to the left pane. Now, double-click your ROMs directory in the left pane, select a ROM file in the right pane, and click the OK button to start the game! Figure 4-33 shows Gens in action.

Monk and Monkeys running under Gens

Figure 4-33. Monk and Monkeys running under Gens

If you do not like Gens, here are some other Genesis emulators that run on Linux (and other Unixes, too!):

For more Sega emulation goodness, check out:

Other Systems

As the serious console connoisseur knows, there are more systems out there than I have talked about in this hack, and some of them are worth playing. There are also emulators for newer systems that will require some serious horsepower and a good 3D graphics card to run. So reach, if you will, into this emulator grab bag:

Josh Glover

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